Connector switch



e. A. vAwocnowsm.

c onmzmoa SWITCH. APPLICATION FILED AU G.I, I917.

Patented July 25, 1922.

2 SHEET-SHEET 1.

G. A. YANOCHOWSKI.

I CONNECTOR SWITCH. APPLICATION FILED AUGJ, 1917.

1,423,891 K Patented July-25, 1922.

2 S EETSSHEET 2.

STA

res e sNT OFFICE, 1

GEORGE A. reu cnowsxl, 0F cnlqeso :IILLINOIJS, ASSIQNQB so KEILOGG ,SWITCH- B RD AND seer-Ly :GOMBANYL or cs Ase -ttn q s a gqeroamon or Itin- NOIS.

, semssm wl s s eetie-pf mm r Pa ented Jiulyr25, 1922,

Application file-d: A ugnst 1, Serial No. 183,870.

To aZZw/zom z't may; coq ceq' 'nf I Be it known that I, GEO GE'A. Yancoi-iowsnna citizeno't' the UnitedSta tes of America, residing in Chicago; county Cook State of Illinois, ime invented certain new and useful Ianprovements in Qonnector Switches, of which the'folloiv'i ng is a specification. i i My invention relates to telephone exchange systems ot' thekilid in which autoinatic switches are mployed new exchange or central. oiiice forestablishing connections between subscribers lines, and relates in ore particularly to systemsoftlie t-IV O JYlT6 bXpQ which employ switches J ofthe two-diinension type.

The general objectof ny,invention is to provide ,an improved circuit arrangement for a connector switch of the-class described above. I Q

One of the features of my-invention is the provision of an irnproved test arrangeinent for the connector switch, a in which the busy control relay locks up soy (er a lloca l circuit, independent of: the busy potential upon the busy contact engaged the connector switch and the test conductor ofthe .connector switch is interrupted .to disconnect the test mechanisin of vthe ,connectorsi iitch.

Another feature vofiny invention ,islthc provision of a novel, simple, and eflicient arrangement I whereby automatic ringing" is furnished with a lninin um amount da peratus. i Y

A further feature of my imrention is the provision of means for instantaneouslycutting; offthe ringing currentfroni the called subscribers line Whenthe called subscriber responds to a call. 7

The above and otherfeatures-of ny in vention will be hereinafter described,in the ensuingspecification, tt-DCIIIIOIG particularly pointed out in the. appended claims.

For a better understanding of any invention, reference may be had to the accompanying drawingswhichcomprise, Part 1 and Part 2. In order to more fully un derstand the circuits as pointedout Part to be placed to the rightofPa -t 1,:to form a continuationthereofand a completecircuit. In Pa-rt's'land 2; I have-diagrammatically illustrated the complete :circuitarrangenicnt necessary for connect n a. goaliing subscriber to a calledsubscriber, The

circuit shows a calling SubS gi ition A terminating in an individual line switch B,

which line switch Bis adapted to connect with air-idle first selector C. The first selector in turn is: adapted to connect with the idle connector -D,]and the connector' D is adapted to connect Witlrthe terminals o fthe called substation .E. The called substation E also terminates in an individual line sWitchBH The substation A includes the usualtalk- 111g equipmennof acommon battery' telephone w iththe additioi jofa calling device CD adapted tObreakthe continuity of the Subscribersline circuit. The circuit forthe subscriberssubstation AWill be carried through i a series of continuations, finally establishing connection more muedsnbscribens telephone as The;1ine switchB as illustrated is of the self-restoringfjype of individual switch and ispr'oyided with a'rotary shaft that carries a private met wiperfi mm pair of line wipers 3 and lf A lineielay LRis p1 6- vided which is energized "oy'er thesubscrib ersline conductors in series. cu't' ofi'relaIyQOis also provided for disconnecting the subscribers line circuit/from the lin'relay .and for connecting the switch Wipers to the subscribers line circuit A rnot orniagnet 9 is pro'videdfor stepping the sw tcllwip i Mai 1 st p y' thif e the inedium of ratchet and paa l niec ha "sin oyer thebank contactsffii 6 andj'to an dle set. of bank contacts ieading to an idle first selector. Anloff norn al'switch' ON is proyided w hich is actuated upon the first; step f th wip r Off notma The w ch. li-1, p ov ded with a Pa O n e e l e f clf ec 15 and 16 which'a-re adapted too perate with the off-normal contact iipon the first niovement of the switchwiper's from normal position. The switch] contacts 15 and 16 are restored to their norrnal positionby-the energizationofth cutoif vrelay:( T'Oand are caught in. their: normal pos'ition yyhere they are held, until the switch shaft and ;Wip ers return to nornoal, at p which amen 1e said springs 15 andilti are placed lin condition to be operated again by the first noyen ent of .the switch shaft frorn normal. The seqa relay controls a hold ngv pawl in such a'gnantest -"i11 k i hii be -r and wipers to normal, The motor magnet f) besides being provided with a driving pawl for rotating the switch shaft also controls a pair of contacts 8 and 13. The switch wipers are spring restored and are adapted to be released to normal When the cut-off relay CO is tie-energized.

The circuits shown for the selector C and connector D are adapted to work with a switch structure similar to that shown in application H. H. Ide, Serial No. 175,364, filed June 18, 1917. i It is to be understood, however, that the circuits shown may be used in connection with various other switch structures of the prior art.

The first selector C comprises an impulse relay IR, which relay is energized and de energized by impulses from the calling device CD at the calling substation A, and the energization and de-energization ot the relay IR brings about the actuation of the primary magnet PM to step the first selector switch wipers 36, 37 and 38 in a pri mary direction to a certain group of contacts. A secondary magnet S11 is provided for said selector which automatically steps the wipers 36, 37 and 38 in a secondary direction over the contacts 47, d8 and 4:9 in the selected group to seek an idle set of contacts leading to a connector, as D. A switching relay T is also provided which when energized extends the connec tion of the calling substation A tothe idle connector D. Primary and secondary offnormal contacts PON and SON, respectively, are provided. The said primary offnornial contacts PON assume their alternate position on the first stepof the wipers in a primary direction, and the secondary ofiinormal contacts SON assume their alternate position upon the first step of the wipers in a secondary direction.

The connector switch D is provided with an impulse relay 1R responsive to the impulses of the calling device CD at the calling substation A, which relay 1R brings about the actuation of the primary magnet PM to step the connector switch wipers 63. G l and in a primary direction to a certain group of contacts containing contacts of the called line E. A. switching relay SW is provided which energizes upon the termination of the first set of impulses to connect the secondary magnet SW1 in circuit with the impulse relay 1R to be actuated by the energization and the de-energization thcreo'l to step the connector switch wipers 63, G-l and 65 over the contacts 78, 79 and80 in the selected group to seek the contacts of the called line. A test control relay'TCR is provided which assists in the test of the called line as to its idle or busy condition. and a test relay TR is provided which is actuated upon connection witha busy called line through the agency of the relay TCR.

The said relay TR- operates to connect busy-. back apparatus BB to the calling substation to notify the calling subscriber of the busy condition of the called line and disconnects the relayTCR from the test wiper 63. A ringing trip relay HT is also shown which is operated when a called subscriber removes his receiver in response to a call, the said relay opening the ringing circuit to disconnect the ringing current from generator GR which passes through the interrupter I. Should a called subscriber remove his receiver during either a ringing or a silent period, the ringing current is immediately disconnected, as will be more fully hereinafter described. The relay ET is provided with a locking winding to prevent a reapplication of ringing current to the called subscribers line prior to a disconnection of the connector D from theline of the called subscriber. With this ringing arrangement. it is only necessary to provide one control relay for the ringing current. A back bridge or supervisory relay SR is also provided which operates upon the actuation of the ringing trip relay RT. Primary and sec ondary oif-normal contacts PON and SON are provided and assume their alternate positions, respectively, upon the primary and secondary movements of the wipers 63, 6s: and 65.

To the right of the drawing in Part 2, I show a called substation E, similar to that of A, the said subscriber being provided with a line switch B similar to line switch B.

Having described in general the apparatus embodying my invention, I will now de scribe more in detail the operation of the system as illustrated. Assuming now, For instance, that a call is to be traced from the calling substation A to the called substation E, upon the removal of the receiver by the subscriber at the substation A, a circuit for the line relay LR of the individual line switch 13 is established, this circuit being traced from battery through the winding of relay LR, normal contact 8 oi relay 9, normal contact 10 of the oilinormal switch ON. normal contact 11 of relay CO, and through the closed contacts of the switch hook at substation A to ground at normal contact 12 of relay CO. The line relay LR. upon energization, establishes an energizing circuit for the relay 9, which may be traced from battery through the winding ol said relay 9. normal contact 13 of said relay 9, and alternate contact 14 ot relay LR to ground. Relay 9 upon energizing opens the circuit of relay LRat its contact 8 and rotates the switch shaft and its wipers one stepv A further result due to the energization of relay 9 is the opening of its own circuit at its contact 13 as well as at contact 14: of re ay LR. Upon the first step of the switch shaft, the

' e s-tee cit-normal contacts ON assume their alternate position, and contacts 15 and 15 are also moved to their alternate position. The closure of alternate contact 15 places a ground or busy potential upon the private connector bank contacts of the callingline. The opening of alternate contact 14 of line relay LR brings about the de-energization of the relay 9, and should the private wiper 2 of the line switch B engage a busy contact 5 upon the first step of the wipers, a substitute circuit for the line relay LR is established, traced from battery through the winding of relay LR, normal contact 8 of relay '9, alter nate contact 10 of off-normal contacts ON, and alternate contact 16 to ground at the busy Contact 5 engaged by private wiper 2. The closure of the alternate contact 14 of the line relay LR again establishes a circuit for relay 9, as previously described, causing the switch Wipers to take another step and engage the second set of contacts 5, 6 and 7. If the next private contact 5 is busy, relay 9 and line relay LR are again energized and de-energized to step the wipers 2, 3 and 4; step by step until an idle private contact 5 is encountered. l Vhen the contacts leading to an idle first selector C have been found, the line relay LR tie-energizes, bringing about the de-energization of the magnet 9. The closing of normal contact 17 of relay LR establishes an energizingcircuit for the cut off relay CO traced from battery through the winding of the said relay CO, conductor 18 and normal contact 17 ot-relay LR to ground at alternate contact 15. The energization of the relay CO brings about the restoration of the contacts-15 and 16.to their normal vposition, opening the initial energizing. circuit of the relay CO. As before stated, the operation and restoration of-the contacts 15 and 16 to their normal position causes said contacts to be locked in such position by a spring-controlled member that retains contacts 15 and 16 in their normal position until the switch shaft returns to normal and moves the said spring-controlled member back to its normal position, thereby placing contacts 15and 16 in a condition so that upon the next first rotary step of the shaft from norm-ahthe' said springs 15 and 16 are permitted to move to theirwalternate position. The return of the spring-controlled'mernber to normal also restores the off-normal contact 10 to its normal position.

The relay CO, being slow to release, has a substitute circuit established for it, as will bejpresently described, before it has had time to dc-energize and permit its contacts to return to normal. The relay CO is adjusted notto pullup until relayLR- de-ener- ,mary direction to the'third group of congizes-and a steadyflow of currentis established through its Winding. The wipers 3 andlhavmg engaged contacts 6 and 7 ct theidle first selectorC bring about'the ener;

from battery through the upper winding of said relay 24, over conductor 25, and through alternate contact 23 of relay IR to ground at normal contact 26 of primary off-normal contacts PON. An energizing circuit for the relay 27 is also established when relay IR is energized, over a circuit traced from battery through the upper winding of the said relay 27, over conductor 25, and through alternate contacts 23 of relay IR to ground atino'rmal contact'26. The closing of alternate contact 28 of relay 27 establishes a sub- Stitute circuit for the cut-off relay C0 of the line switch B before it has had time to deenergize, said circuit being traced from battery through the winding of the relay CD, conductor 18, normalcontact- 17 of relay LR, normal contact 15, alternate contact 29 of relay CO, conductor 30, wiper 2, contact 5, conductor 31, and alternate contact 32 of relay 24: to ground at alternate contact 28 of ates the calling device CD to send three" impulses of current over the line, which impulses bring about three successive energizations and .de-energizations of the impulse relay IR. Upon. the first de-energization of the impulse relay IR, the circuit for the primary magnet PM is established, traced froin'battery through the winding of the magnet PM, normal contact 33 of the secondary off-normal contacts SON, conductor 34L, normal'contact 23, and conductor 25 to ground at alternate contact 35 of relay 24-. The primary magnet PM is energized and de-energized three times due to the open- 'ing-and closing of contact-23 of relay IR,

which magnet operates to step the 'wipers 36, 37 and .38 of the first selector C'in a pntacts corresponding with the desired. second selector or connector. ..Arter the last 1maulse the rela 27 de ener izes' due to a cir-; l 7 v V. a a,

(iii

cuit being closed through the lower winding of the relay 2T, traced from battery through the lower winding of the said relay, normal contact 39 of relay SM, alternate contact c0 of relay IR, and alternate contacts 41 and so of primary oft-normal contacts PON to ground. The said primary oft-normal contacts FUN move to their alternate positions upon the tirst step of the wipersot the lirst selector C. The energizing circuit 'lor relay 2'? just mentioned is closed upon the lirst step of the wipers oif normal, but the relay 2? does not de-energize during the sending or impulses, due to the construction and adjustment of the said relay 2?. The dill'erential relay 2'? only receives short impulses of current during the operation of relay IR which do not affect the relay sufiiciently to cause it to de-energize. As soon as the above-mentioned circuit through the lower winding of relay 2? is closed and receives a steady low of current, the said ditlerential relay 7 tie-energizes. The opening o'l' contact 28 of relay 27 disconnects ground from conductor 31 at this point but a substitute ground through alternate contact 26 ot the primary oft-normal contacts PON is substituted before said relay 27 deeuergizes. The ground over conductor 31 also places a busy potential upon private contact 5, preventing any other individual line switch from engaging multiples of said contact. Owing to the construction and adjustment of differential relay 2 it is not tie-energized during the rapid operation of relay IR. Upon the de-energization of the relay 2?, an energizing circuit for the relay a2 is established, traced from battery through the winding of the said relay 4-2, normal contact a3 of relay T, normal contact all of secondary magnet SM, normal contact l5 ot the secondary oil-normal contact SON, normal contact 28 of relay 27, and alternate contact 32 of relay 24 to ground at alternate contact 26 or primary oil-normal contacts PON.

The energization of the relay 42 establishes an energizing circuit for the secondary mag net SM, traced from battery through the winding of the said magnet to ground at alternate contact at of relay 42. Secondary magnet SM energizes and steps the wipers 36, 31' and 38 one step in rotary secondary direction to engage the first set of contacts l7, l8 and L9. The energization of the secondary magnet SM brings about the restoration of the relay 4-2 due. to the opening of normal contact at of said magnet SM. The opening of contact 39 of magnet SM again permits the energization of relay 27 by opening the circuit of its lower winding. The restoration ot the relay 42 opens its alternate contact ac, bringing about the restoration of the secondary magnet'SM. Upon the first step oi the wipers 36, 37 and 38, the

secondary oil-normal contacts SOIN assume their alternate position, and the opening of the normal contact d5 of secondary oil-nornial contacts SON removes the initial ground from the relay 42; and should the private viper 36 of the first selector C engage a contact leading to a busy connector D, an energizing circuit for the relay l) again established over a circuit traced. from battery through the winding of the relay 42, normal contact d3 of relay T, normal contact all of magnet 5M, alternate contact 50 oi? relay 24, alternate contact 51 of relay 2? and wiper to the grounded busy contact ll The closing of the alternate contact 46 of relay d2 brings about the energization of secondary magnet SM, as before described. The relay l2 and magnet SM are thus alternately energized and tie-energized to step the wipers 36, 37 and 38 in a secondary direction to seel; the contacts of an idle connector switch D1 When a contact ll leading to an idle connector as D is encountered by the wiper 36, the energizing circuit ol the test relay a2 is maintained opened, thereby prerenting further energizations ot the second a ry magnet SM. It will thus be seen that by this see-saw action of relay l2 and magnet SM a positive driving operation of the secondary magnet is secured, and that it is impossible to stop the selector C on a busy contactor to drive the said selector past an idle contact because unless relay a2 is encrgized magnet SM cannot be energized and relay l2 can only be energized when magnet SM is at normal and private wiper 36 is resting on a busy contact.

The relay 27 does not tie-energize during the secondary movement of the wipers, due to its adjustment and the rapidity oli'the interruptions of normal contact 39 of secondary magnet SM. The closure of normal contact of secondary magnet SM, after its last de-energization, closes a circuit for the lower winding of the relay 27 over a circuit previously described, and due to its dillerential action it ale-energizes. Upon the restoration of the relay 27, an energizing circuit for the relay T is established, traced from battery through the winding of the said relay T, alternate contact l5 of the secondary off-normal contacts'SON, normal contact 28 of relay 27, alternate contact 32 of relay 2a to ground at alternate contact 26 of primary oil-normal contacts l ON. The opening of nor: mal contacts 20 and 21 of relay T opens the energizing circuit o'lthe impulse relay 1B. The relay IR upon ale-energizing closes a circuit through the lower winding ot' the relay 2-}: traced from battery through the said lower wmdmg'normal contact 23 ot said relay IR, to ground at alternate contact no of said relayQ l. The relay 2d, due to its differential wmdmgs, neutralizes and lit) said relay :2? to restore. The: closing of alternate contacts and 21 ofrelay T extendsthc connection of the calling subscriber A to the idle connector I), engaged by wipers S6, 37 and 2380f selector Cr The closing oi. alternate contactsQO and 21' of relay T brings about the energization of the impulse relay 1B of connector D over a circuit traced from ground through-the right-hand winding: of-sai'd relay-1R bank contact a9. wiper 238, alternate contact 21 of relay T, bank contact 7.; wipen ig alternatc contact, 11 ofrelay CO, through, the

' substation A, the alternate contact 12 of relay CO wiper 3, bank contact 6; alternate cont 1101:20 0)? relay T, wiper 37, bank con' tact 48, and through the left-hand Windin of the interrupter relay IR to;battery and ground. The restoration ofthe: relay 2-1- o'fqthe first selector C opens theinitia'l energizing circuit of relayT of. the first selector C, but the relay-T being slow to release has a substitute circuit established for it, traced from battery through th'e winding of said relay; itsalternate contact 52, wiper 36, bank contacta'f, conductor 53,

' andconductor 54: to ground at" alternate contact 55 of the impulse relay 1R before :it has had time to -d'e-energizei The said relay T'rem'ains energized until thetermination of the conversation.

The energization of the relay 1R brings about the energization of the relays 56v and 57, the circuit of relay 56-extending from battery t-hrouglrthe right-hand winding of said relay; normal. contact 58 of the primary off-normal contacts PON conductor 52--and conductor 54- to ground at alternate contact 55 Of relay IR. 'The-circuit for relay- 5'? extends from'battery through the lower windingbfthe relay 57 conductor 59 conductor 6O, and alternatecont'a'et 61 oi? the relay IE to ground at alternate contact 55 off-impulserelay. 1R Upon the energization of relay 56,; a" locking circuit is closed for the said, relay :56 extending from battery througlrits alternate contact 62 to-groundr A 'circuitis closed' through the upper winding. of relay at contactlOO of relay 56 when" it energizes. The: closing. of thiscircuit causesthe relay-57 to be de-- energized due to its differential"'construc= tion. However; the de energization of' re lay is without effect at this time because the instant the impulse relay IR is deenergized when the subscriber starts to send impulses, the circuit through the lower winding of relay 5? is opened and thesaid rel instantly energizes and remains in its energized condition during. the period that the-impulse relay IR? is operated." i

The subscriber now operates his calling device-CD to send the second series of imftraced from battery through the winding of the said magnet. normal contact 66 of switching relay SW, conductor 67, alternate contactGS otrel'ay 57:; normal contact 161 of relay 1R conductor, 54, conductor 53,,and normal contact 58 of the primary off-normal contacts PON to ground at alternate contact 62-of relay 56. The primaryofi' normal contacts PON assume theira'lternatejpositions upon-the first step of the wipers oft normal. The openingot the primary off-normalcontact 58 substitutes the ground fed from contact 69- of relay 70 for the ground fed through contact GZot relay 56. After" the last iinpulseot the seriesxhas been sent; the steady flow of:- current. through both windings of relay'fi? causesthe said relay 57-, due to itsdifi'erential action, to, neutralize and restore itscontacts to normah Relay 57- does noti'restore during the sendingwotimpulses due to its adjustment, construction and the rapidity of the interruptions otcon'liact 61-. The closing of normal contact 71' of relay 57 brings about the energization of the switching-relay Sivtraced from battery through the winding of said relay Sil the make-be fore-break-contact 72 ofsaid relay SlV. normal contact'73'of secondary off-normal con tacts SQN conductor T l normal' contact 71 off relay- 57, and conductor T5 to: ground at alternate contact 76 ot prii'nary otlnormal contacts PQN the said primary oil-normal contacts PON having been moved to their alternate position on thefirst step ofthe wipers 63, 64 and of the connector switch 13.5 The closing of alternate contact S5 of relay Sll closes a locking circuit foritselt traced from battery through the winding of relay SW alternate cont'act85, conductor 86,- no'ij'1n.al uco ntact 8? of relay TOR-i conductor 7 5 to groundhat alternate contact 76 primary otE-normal contacts PONR The said relay SlV remains energized until the relay TOR is actuated, as will be presently descril'ied. The closing of alternatecontact 66 ot the switching-relay 'SFW now renders the secondary magnet SM operative so that when the calling subscriber at the substation A actuates his call device again to sendthe last set ot impulses, which we-have assumed are fi'vein numb r, the said magnet SM' Will be energized and de-energized by the impulse relay 1R five'times over a circut traced from batterypthrough the winding of the said magnet SM alternate contact 66 of'rel'ay SW, conductor 67 alternatecontact 68' of IE-K lay 57, normal contact 61 of relay 1R conductor 54, conductor 53, alternate contact 58 of the primary off-normal contacts PON and conductor 77 to ground at normal contact 69 of relay 70. The secondary magnet SM now steps the wipers 63, 64 and 65 in a secondary direction to engage contacts 78, 79 and 80 of the called line. Upon the first impulse of the last set, that is, upon the opening of contact 61 of relay IR 'the relay 57 again energizes to permit the secondary magnet 8M to be operated, and after the last impulse the relay 57 is again de-energized by having a circuit closed through its lower winding, as previously described. The restoration of the relay 57 closes a circuit for the relay TCR traced from battery through the winding of the said relay, conductor 81, alternate contact 82 of relay SW, alternate contact 73 of the secondary off-normal contacts SON (said contacts having been moved to their alternate position upon the first step of the wipers in their secondary direction) conductor 74, normal contact71 of relay 57, conductor 75 to ground at alternate contact 76 of the primary off-normal con tacts PON thus causing the said relay TCR to energize. The relay TCR, upon energiz ing, opens the locking circuit of relay SVV' at its contact 87, permitting the said relay to de-energize. The relay SW tie-energizing opens the circuit of the relay TOR at its con tact 82, leaving the relay TCR dependent upon the potential found on the private contact 78 of the called line.

The closing of alternate contact 90 of re lay TCR connects the test relay TB in multiple circuit with the said relay TCR to'the test wiper 63, the circuit of the test relay TR being traced from battery through the winding of said relay, its make-before-break con tact 94, conductor'95, normal contact 82 of relay SW, conductor 81, alternate contact 90 of relay TOR, conductor 91, normal contact 92 of relay TR, conductor 93 to the test wiper 6-3. The circuit of'the relay TOR may be traced from battery through the winding of the said relay, its alternate contact 90, conductor 91, normal contact 92 of relay TR and conductor 93 to the wiper 63.

Called Zine idle.

-Assuming that the called line is idle, private contact 78 of the called line will have a battery potential upon it and the relay TR will not be energized but will remain at normal and therelay TCR failing to find a ground upon wiper 63 returns to normal, having its initial energizing circu1t opened at alternate contact 82 of relay SlV, as before described. I

The relay T CR (ls-energizing brings about the energization of the relay over a circuit traced from battery through the cut-off relay (70 0f the individual line SWitQh B bank contact 78, through wiper 63, conductor 93, normal contact 92 of relay TR, conductor 91, normal contact 90 of relay TCR,

conductor 96, normal contact 97 of relay SW conductor 98,through the lower winding of'the relay 70, conductor 99, to ground at alternate contact 100 of the relay 56. Relays-7O and CO energize over this circuit. Relay CO upon energizing, removes the called subscribers control of the line switch B 'The closing of alternate contact" 101 of relay 70 short-circuits the lower winding of the said relay and feeds ground to the cutofl relay C0 of the line switch B and at the'same time supplies the busy potential to the multiple private contacts of the called line. 7 The closing of alternate contact 102 of relay 70 closes a'circuit through the upper windin of said relay 70 traced from battery througi its winding, the alternate contact 102 of said relay 70, and conductor 99 to ground at alternate contact 100 of relay 56. The closing or alternate contact 103 of the relay'70 closes a circuit for ringing current from generator GR to signal the called subscribers substation, the path of said ringing current being traced from battery 125 through the ringing generator GR, through the live segment of the interrupter I, through thewinding 104 of ringing trip relay RT, conductor 105,alternate contact 103 of relay T0, conductor 106, normal contact 107 of re lay RT, wiper 65, contact 80, through the call bell and condenser of the called substation E, back through contact 79, wiper 64-, normal contact 108 of relay RT and conductor 109, to ground at alternate contact 69 of relay 70. The ringing current is intern'iittently connected to the called line due to'the constantly rotating interrupter I, thus bringing about an intermittent actuation of the call. signal at the called subscribers substation E; The interrupter I is so arranged that ringing current from the generator GR and battery 110 are alternately connected to the called line so that should the subscriber answer in either a silent or a ringing period, ringing current is instantly disconnected, thus eliminating the undesirable feature of ringing the answering subscriber. at the called substation inthe ear should the subscriber remove his receiver during a ringing period; During the ringing and silent pcriods, and before the subscriber at the called substation E answers,- the condenser at the said substation prevents a flow of battery through the-winding104l of the relay RT. The subscriber in response to the call signal removes his receiver, and should he remove it during a live period the combined generator and battery current of the generator GR and battery 125 bring about the energi zation of the relay RT over a circuit traced from battery 125through the said generator GR, through the interrupter I, the upper winding] 04 of relay RT, conductor 105 alternate contact 103, conductor 106, normal RT energizes over the circuit just traced and interposed.

closes a lockin circuit for itself. traced from battery through the lower winding'lll of relay RT, its alternate contact 112, and conductor to ground at alternate contact 76 of the primary off-normal contacts PUNK Should the subscriber remove his receiver from the switch hook during a silent-period, the relay RT will energize over a circuit frombattery 110 through the live battery se -uifents of the interrupter I, the upper wu'iding 10a of relay RT and over the previously described path to ground at alternate contact 69, which causes the relay'R-T to energize and close the locking circuit for itself through its winding 111, as-before described. -Thus it may be seen that'ringing current is instantly disconnected vfrom the called" line either during'live or silent periods by the opening oi? contacts 107 and 108 of relay RT. Upon the energization of'the relay RT, an energizing circuit for the supcrvisory relay SR is established traced from battery through the lower winding of said relay SR, alternate contact 107 of relay RT, wiper 65, contact 80, through the substation back to the contact 'ZS), wiper 6 1, alternate contact 108 of relay RT and through the upper winding of the relay SE to ground. The subscribers are now in eonx'ersational circuit and the talking circuit may be traced over the heavily marked conductors, the said conductors-having the condensers K and K The subscr'bers having finished conversation, and assuming that the subscriber at the substation A isthe first to replace his receiver upon its switch hook, the opening of the switch hook contacts brings about the de-energization of the impulse relay,

"IE of the'connector D. The-restoration about the eneigizatioiuotl the-secondary magnet SM. 'The relay 42 and the sec- -ondary magnet SM are alternately energi zed :and it eeenergi-zed, iasiipireviously. described to normal.

nate contact 26 ot' the primary olt-norn contacts 'PON opens the energizing mean of the cut-off relay CO 01 the indiviruial line switch B. The restoration of theacutmii relay C0 of the line switch. B brings about the restoration to normal of the wipers 2, 3 and a 01 said individual switch B. The subscriber E placing his receiver upon the switch hook interrupts the circuit 01" the relay SR of the connector D at the switch hook contacts, causing the said relay to tie-energize. The closing of normal contact 130 of relay SR closes a eircuit through the lefthand winding 01 the relay 56 which may be traced from battery through the said lciithand winding of relay 56 through its alternate contact 131, conductor 132 normal contact 130, and conductor 133 to ground at normal contact 55 of the relay 1R Due to 56, the said relay neutralizes and restores The closing of normal contact 134: of relay 56 closes the circuit oi secondary magnet SM which may be traced from but tery through the winding of said secondary magnet SM conductor 135, normal contact 13 1 of relay 56, alternate contact 136 01 primary cit-normal contacts PO N through the interrupterI to ground. The secondary magnet SM thus steps the wipers 63, '64 and 65 beyond the last set of contacts in the group, and the wipers then restore to normal from this position. The restoration of the relay 56 also brings about the opening of the circuit of the. relay '70 at alternate contact 100,bringing about the restoration of the said. relay T0. The primary off-normal contacts PON having restored upon therestoration out the switch, the opening of alternate contact 76 oil? the contact SPON brings about the restoration of therelay RT.

The relay 56 also causes the de-energization of cut-off relay'CO of the line circuit B which is associatedwith the called subscribers substation E. All of the apparatus usedin establishing theconneetion be tween the calling subscriber at the substation Aandthe called subscriber at the called substation E is now at normal andsavailable for use in establishing other connections.

Assuming now that the subscriber at the called substation E is the first to replace his receiver upon the switch hoolr. the Opening of theswitch hook contacts at thesubstatiou E brings about, the de energiaation m the relay SR. Nothingelsehappens at this time as the relay 1B is still ,maintaincd energized (over i the line of the. calling subrupts the circuit of the impulse relay T r described.

station A. The calling subscriber at the substation A. replacing his receiver intgi; at the switch hook contacts. The relay de-energizing, closes a circuit through the left-hand winding of relay 56. causing the said relay to ole-energize, as herein-before The restoration of the individual switch B, first selector C and connector D is the same as previously described from this point on.

Should the called subscriber E "tail to re place his receiver upon the switch hook after the conversation is terminated,the replacing of the receiver at the substation A, brings about the de-energization of the impulse relay D3 of connector D, the same as before, and the opening of alternate contact 55 of the impulse relay 1R opens the circuit of the relay T of the first selector C, as before described, and causes the release of the selector C and individual switch B. The subscriber at the called substation failing to replace his receiver upon the switch hook permits the continued energization ot the relay SR, thus holding contact 130 of said relay in its alternate position, preventing the diilcrentiallywound relay 56 from restoring to normal and closing the energiz ing circuit for the secondary magnet 8M The relay 57 energizes when the'impulse relay 1R drops back but is immediately restored to normal due to the closure of an energizing circuit through the lower winding of the said relay 57, which may be traced from battery through the lower winding of the relay 57, conductor 59, conductor 60, alternate contact 180, conductor 133, to ground at normal contact 55 of the now restored impulse relay 1R The relay 57 being differentially wound restores to normal, and the closing of normal contact 140 of said relay 5? places a ground upon the private contact of the connector D over acircuit which may be traced from ground to alternate contact 76 of primary off-normal contacts PON through conductor 75, normal contact 71 of relay 57, conductor 74:, alternate contacts 73, normal contact 140 of relay 5?, alternate contact 14-1 of secondaryott-normal contacts SON and conductor 53 to the privatecontact 47. The placing of the busy potential upon the private contact prevents any first selector switch C from engaging the contacts of this busy connector.

Called Zine busy.

Assuming now that the called line is busy, the operation of the circuit isthe same up to and including the time when the relay TCR energizes, as previously described; The line being busy, private contact 78 has a busy potential placed upon it, thus closing the multiple circuit for the relay TCR and the test relay TR, the circuit of the relay TCR being traced from battery through the winding of the said relay TGR, its alternate contact 90, conductor 91, normal contact 92 of relay TR, conductor 93, to the busy ground ed private contact 78. The circuit of the test relay TB is traced from battery through the winding of the said relay TB, the makebefore-break contact 94: of said relay, conductor 95, normal contact 82 of relay SW, conductor 81, alternate contact of relay TCR, conductor 91, normal contact 92 of re lay TR, conductor 93 and wiper 63 to ground at busy private contact 78. The contacts 94 and 92 of the relay TR are so adjusted that the alternate contact 150 makes before the contact 92 breaks, thus closing a locking circuit for relay TR through its alternate contact 150 before the normal contact 92 of the said relay breaks. The locking circuit of the said relay TR extends from battery through the alternate contact 150 of the relay TR, conductor 151, to ground at alternate contact 76 of primary off-normal contacts PON The locking circuit for the said test relay TR is independent of the grounded private contact and the opening of the normal contact 92 of the relay TR opens the circuit for the relay TCR which restores to normal. The falling back of relay TCR does not affect relay 7 0 due to the fact that the test conductor 98 is held open at contact 92 of relay TR. The locking circuit for the test relay TR is thus independent of the busy grounded contact 78. This arrange- 100 ment does away with the method usually employed of locking the busy relay up to the busy private contact of the called busy line. The closing of alternate contact 152 of relay TR connects the busy-back signal BB to the calling line to transmit a busy signal to the said calling subscriber at the substation A, thus notifying him of the busy condition of the said called substation E.

The calling subscriber now replaces his receiver upon the switch hook, bringing about the de-energization of 1R The relay 1R restoring opens the circuit for the relay T of first selector C, which closes the circuit of the secondary magnet SM, as previously described, thus bringing about the release of the first selector C and individual switch B. The relay 1R deenergizing brings about the restoration of the relay 56, due to the fact that the relay SR is not energized. The closing of normal contact 134 of the said relay 56 closes the circuit for the secondary magnet SM which magnet steps the wipers 63, 641: and 65 beyond the last set of contacts. The wipers then restore to normal. Primary off-normal contacts PON and secondary oif-normal contacts SON are also restored. The apparatus used in this busy connection is now at normal and available for use in establishing other connections.

Should the called line become idle during the time of the transmission of the busysignal and the time the calling subscriber replaces his receiver, nothing happens as the contact 92 of relay TR is in its alternate position,'

preventing the energizationzof relay 70, and

thus preventing ringing current'lrom being exact disclosure but aim to cover all such changes and modifications as come within the spirit and scope of the appended claims. Havingfdescribcd my invention what I claim as new and desire to secure by Letters Patent is:

1. A telephone system including a called subscribers line, a connector switch for tending a connection to said called subscribers line, a test circuit for said connector switch, a test control relay and a test relay for said connector switch, means for momentarily energizing said test control relay, contacts controlled by said test control relay for connecting said test relay to a test contact of the called line, and means controlled by said test relay if said called line is busy to'interrupt said test circuit.

2. Atelephone system including a'called line, an automatic connector switch provided w th a line relay controlled over thetwo SlClQSOTE said calling line in series for 8X1 tending connection to said called subscribers line, a differential secondary relay for said connector switch, testing mechanism for said connectorswitch-including a test conductor, means controlled by said differ ential relay for associating said testing mechanism with said called subscribers line,

and means controlled by said testing mecha-,

nism for niaintaini'ng saidtest conductor open ifsaid'called line tests busy.

5. A telephone system including a calling and a called subscribers line, an automatic connector switch provided with a "line relay controlled over the two sides of the callmg line in'seriesfor extending-a connection to said called subscribers line, a difierential secondary-relay for said connector switch, testing mechanism-for saidconnector switch includin'a test conductor, meanscontrolledby said c ifferential relay for associating said testing mechanism with said-called sub-p scribers line over said test conductor, means controlled by said testing mechanism. for

opening said test conductor, and a locking ClIClllt for SitlCl test mechanism ndependent of said test conductor.

6. A telephone system including a calling and a called subscr-ibers line, aside switchless connector switch for extendinga connection to said called line, a line relay individual to said connector switch controllable subscribers'line, a connector switch for ex tending a connection to said called subscribers' line,-testing mechanism for said connector switch including a test conductor and a test control relay, a test relay for said connector switch, means forenergi'zin'gsaid test control relay, contacts controlledby said test'control relay for connecting-said test relay to said test conductor, and means controlled by said test relay for interrupt-- ing the said test conductor if said called line is busy.

3. A telephone system including a called subscribers line, a connector switch for-eX tending a connection to said calledline, testing mechanism for said connector switch in; cluding a test conductor and a pair o'tcooperating relays, means for energizing one of said relays whereby said pairof relays are connected to said test conductor, sel1 locking means for maintaining the other of said relays in an energized position'ii said called line tests busy, and means controlled by said lastrelay for interrupting the circuit of said test conductor.

4. A telephone system including a calling subscribers line and a called subscribers over the two sides-of said calling subscribers line-in series, testing mechanism for said connector'switchincluding a test conductor and a test relay, means controlled by said line relay for associating said test relay with said called subscribers line, self-locking means for said test relay for holding it in.

an energized position if the called ;sub

scribers line test busy, and means controlled. bysald test relay for maintaining said test conductor open until'said connectoris'ree leased to normal. U 1 U 7 A telephonesystem including a calling and a called subscribers line, an automatic side-switchless connector switch provided with a line relay controllableover the two sides of said calling line inseries for'estabe lishing connection .with said called sub- I scribers'line, testing mechanism for said- -connector switch including'a test conductor adaptedto be connected to a test contact of said called subscribers line and a test relay,

means controlled by *said line relay 150mm. necting said test relayto said test contact, a local locking circuit for said relay adapted to be closed ifsaidcalled line tests busy,

and means controlled by said relay for main- I tainingsaid test conductor open until saidconnector switch'is restored to normal.

8. A telephone'system including a calling 7 and a called subscribers line, aconnector nector switch, testing mechanism for said connector switch includinga test conductor, means controlled by said dlfierential relay for associating -said test mechanlsm wit said called subscribers line, and means con-- trolled by said test mechanism for .maintaining said test conductor open if. said called subscribers line-tests busy.

9. A telephone system including a calling .subscribers' line, a connector switch provided with a differential switching relay for establishing connection with said called subscribers line, testing mechanism and a test conductor for said connector switch, means controlled by said differentialrelay for associating said test mechanism with said called subscribers line, and means controlled by said test mechanism for interrupting said test conductor and maintaining it open un til said connector is released if said called line tests busy.

10. A telephone system including a called subscribers line, a connectorswitch for extending a connection to said called subscribers line, a difierential switching relay for said connector switch, automatic ringing mechanism for said connector switch, means controlled by said differential relay for as sociating said ringing mechanism with said called subscribers line, said automatic ri11ging mechanism comprising means for instantaneously disconnecting itself from said called subscribers line when said called subscriber responds during either a ringing or a silent period.

11. A-telephone systemincluding acalling and a called subscribers line, a sideswitchless connector switch, a switch shaft for said connector switch provided with wipers adapted to be moved in one direction to selecta group oi lines and in a plane at right angles thereto to establish connection with said called subscribers line. a line relay for said connector switch controllable over the two sides of the calling subscribers line in series, automatic ringing mechanisnr for said connector switch, means controlled by said line relay for associating said ringing mechanism with said called subscribers line, said ringing mechanism being controllable by the response of the called subscriber to instantaneously disconnect or cut cit the ringing current from the called line..

1:2. A telephone system including a called subscribers line, a con'nector'switch for e:*- tending a connection to said called subscribers line, testing mechanism for said connector switch including a test conductor and a test control relay, a test relayji'or said connector switch, means for energizing said test control relay, contacts controlled by said test control relay for connecting said lay is caused to de-energize and all connector switch. mechanism disconnected from said test conductor, and a local locking cirv cuit for said test relay.

13. A telephone system including a called subscribers line, a side-switc'hless connector switch for extending a connection to said called line, testing mechanism for said con nector switch including attest conductor and a pair or'co-operating relays, means for energizing one ofsaid relays whereby said pair of relays are connected to said test conductor, self-locking means for maintaining the other of said relays in an energized position-if said called line tests busy, and means controlled by said last relay for inter rupting the circuit of said test conductor thereby causing the de-energization of said first relay and disconnecting all connector switch mechanism of the connector switch from the test'contact of the called line.

14-. A telephone system including a call-- ing subscribers line and a called subscrib ers line, a side-switchless connector switch, a switch shaft for said connector provided with contact makers adapted to be moved in one direction to select groups of lines and in another direction in a planeat righ angles to complete connection between said calling and called subscribers lines, a line relay for said connector switch controllable over the'two sides of the calling line in series for effecting such connection, signaling current, a relay, automatic means for intermittently connecting said current through a winding oi said relay to said called subscribers line, said relay being adaptedto be energized when the called subscriber responds during either a silent or ringing periodto disconnect said signaling current'from said called subscribers line.

15. Atelephone system including a calling subscribers line and a called subscrib rs line, a connector switch torus e in extend ing a connect on from said calling subscrib-V ers line to said called subscribers line, a d ii'erential switching relay individual to said connector switch, testing means for said connector switch including a test con ductor adapted to be connected to a test contact of the called subscribe "s line, means controlled by said differentialswitching relay for operatively associating said testing mechanism with said called subscribers line, and means controlled by said testing means for interrupting the said test conductor thereby disconnecting all mechanism of the connector switch from said called sub scribers line.

16. A telephone system including a called subscribers line, a side-switchiess connector switch for connection to said called subscribers line, a differential switching I re-- lay for said connector switch, testing mechanism including a test conductor and a test relay, a circuit for said test relay includ ng said test conductor, and a locking circuit for said testing relay independent otf saio' test conductor, said test relayoperating to interrupt said test conductor -whei1 energized.

17. A telephone system including a called subscribers line, a side-switchless connector switch for establishing connection therewith, a diiferentialswitching relay for said connector switch, a switching relay controlled by said differential relay, a test relay, a test control relay adapted to be energized by an operationof said differential relay, contacts controlled by said'test control relay'for deenergizing said switching relay and for connecting said testrelay and said testcontrol relay in multiple to a test contact of said called subscribers line, whereby; said test relay is energized if said subscribers line tests busy, and a local ;-l'ockiiig circuit for said test relay independentof the energiz-' ing circuit ofsaid test relay. g

l8.- A. telephone system nclud ng calling subscribers line, a side-switchless connector switch for establishing connection therewith, a"differentialswitching relay for Sitld con I16CiOf'SWltCl1',fl switching relay controlled by said differential relay, a testirelay a test control relay adapted to be energized by an operation of said i differential relay, con;- tacts controlledb'y said test control relay for deeenergizing saidswitching relay and for connectingsaid test relay andsaid test con-' trol relay'ininultiple to a test contact of said called subscribers line, whereby said test relay. is energized ifisaid subscribers line tests busy, contacts controlled by saidtest relay for opening the circuit 01"" sai'dtest control relay, and a local locking circuit for said test relay for maintaining said multiple circuit open during the time said connector is in use. i Y 19. A telephone systeniinclucling a calling subscribers line, a connector switch forestablishing connection with said called subscribers line, a differential switching relay 'forsaid con-nectorjswitch, ringing mecha-,-

nism, means controlled by saidvswitching relay for connecting said ringing mechanism with said called subscribers; line if said called subscribers line tests idle, and means controlled by said called subscriber tbr'immediately disconnecting saidringing mechanism from said calle'dsubscrgrbefls line when he responds. I

20. A telephone systeniincluding a called subscribers line, a calling subscribers' line, a side-switchless connector switchoperable over the two-sides of said calling subscribers line in series for connecting tosaid called subscribers line, signalling means associated with said connectorswitch, a trip relay, a

control relay for connecting said signalling means through a windingot' said trip relay to the said called subseribei"s line, means for intermittently applying said signalling.

means to said called subscribers line, and a circuit for said tr p relay CfiGCtlVQ upon a response of the called subscriber during either a ringing or a silent period.

21. A telephone system including a called subscribers line, a side-swi-tchless connector switch torestablishing a connectiontherewith, a switch shaft for said connector having movable contact makers adapted to be movedin a vertical plane toselect groups of.

subscribers lines and to be rotated in a plane at right angles thereto tose'lectthe subscribers lines, a signalling generator, a ringing relay, means for connecting current from saidsignaling generator through the winds subscribers line with said called sub'seriber s line; a line relay for saidconnector switch controllable over the two, sides of said calling l ne in series; a differential switching relay 'for said connector switch controllable by said line relay; automatic ringing mechanism a test control relay controllable by said-switch ing relay and adapted upon being connected to said calledline, it said called line'i's' in an idle condition, to connect said ringing apparatus to said callingsubscribersline, and

a relay controllable over the two sides of the; called linein series to-instantaneously disconnectv said] ringing mechanism when said called subscriber responds.

- A telephone system including a calling and a called subscribers line; an automatic connector switclnprovided with a line relay controlledroverthe two sides of the calling line inseries, for extending a connection to said called subscribers line; a difierential secondary relay for said connector switch for controlling a secondary switching circuit; automatic ringing mechanism i013 said conne ctor switch and means controlled by said line relay for associating said ringing mechanism with saidic alled subscribers line; said ringingmechanism being responsive to a control exercised at the called subscribers substation during either a ringing or a silent interval to disconnect said ringing mechanism from association with said called subscribeflslinel-f over the called subscribers line during either a ringing or a silent interval to disconnel'it itself from association with said called subscribers line, and a dili'erential releaserelay for said connector switch controllable by said line relay tor controlling the release-oi"; said connector switch.

25. A telephone system including a called subscribefisline, a connector switchhaving motion in two directions for extending a connection to said called subscr-ibei."s line, a

line relay tor said connector switch controlled over the two sides of a calling subcscribers line in series, signaling current, a relay, automatic means for intermittently connecting said current through ti -winding of said relay to said called subscribers line, said relay being adapted to be. energized when the calledsubscriber responds during either a silent or a ringing period to prevent a reapplicatiou of signaling current to called subscribers line or to disconnect said signaling current from said called subscribers line, depending upon whether response is had during a ilent or ringing period, respectively, and a dill'erential release relay for saidconnecto r switch control-- lable by said line relay.

26. A telephonesystem including a called subscribers line, a connector switch having motionQin two intersecting planes for extend ing a connection to said called subscribefis line, a line relay controllable over the two sides of a calling snbscribers line in series for controlling the motions said connector switch, a secondary differential relay controllable by said line relay "for assisting in the control of said connector switch, automatic ringing mechanism for said connector switch adapted to be associated wlththe called subscribers line to intermittently operate the call bell-at the called substation, and means included in said ringing mechanism responsive to a control exercised at the called sul station during, either a ringing or silent interval to disassociate said, ringing mechanism from said called subscribers line.

27. A telephone system including a called subscribers line and calling subscribers line, a side-switchless connector switch for connecting said calling'subscribens line to said called subscribers line, a line rela for said connector switch controllable over the two sides of the calling subscribers line in series for effecting such connection, automatic ringing means for said connector, a difiler entially wound relay for said connector switch for controlling the association of said automatic ringing means with said called subscribers line, and meansincluded. in said'automatic ringing means controlled over the called subscribefisline tor disassociating said ringing means from said called subscribers line.

2 8.21 telephone system including sub scribers lines arranged in groups, an automatic side-switchless connector switch for connecting two otsaid subscribers lines 1n telephonic conversation, movable contact makers for said connector switch adapted to be moved in one direction to select groupsoit lines nd to be moved in a second direction in a plane at right angles to the plane of first movement to aline in the elected group,

a line relay for said connector switch-com trollable overt-he two sides of a calling one of said subscribers lines in series for con-- trolling the movements of said contact malters, automatic ringing mechanism for said.

connector switch, means controlled by said line relay for associating said ringing mechanism with the called one of said subscrib;

,ers lines, said ringing mechanism being con? trolled by the response of the calledsub scriber to instantaneously disconnect or precurrent to said subscribers lines in series for controls lin the movements of said contact makers automatic ringing mechanism torsaid connector switch, means controlled by said line relay for associating said ringing mechanism withthe 'calledone of said subscribers lines,'said ringing mechanism includinga relay adapted to be energized when the called party; responds during a ringing interval to disconnect said ringing mechanism from the called, subscribers line,off-normal contacts, and locking circuit for said relay extending through said oil-normal contacts.

30. A telephone system including subscribers lines arranged in groups, an automatic side-switchless connector switch for connecting two of saidsubscribers lines in telephonic conversation, movable contact makers for said connector switch adapted to be moved in one direction to select groups said subscribers lines in tele of lines and to be moved in a second direction in a plane at right angles to the plane of first movement to aline in the elected group, a line relay for said connector switch controllable over the two'sides of a calling one of said subscribers lines in series for controlling the movements of said contact makers, automatic ringing mechanism for said connector switch, means controlled'by said line relay for associating said ringing mechanism with the called one of said subscribers lines, said ringing mechanism including a relay adapted to be energized when the called party responds during a ringing interval to disconnect said ringing mechanism from the called subsc-ribers line, said relay also being responsive during a silent interval to prevent a reapplication of ringing current from said ringing mechanism to said called subscribers line.

31. A telephone system including subscribers lines arranged in groups, an automatic side-switchless connector switch for connecting two of said subscribers lines in telephonic conversation, movable contact makers for said connector switch adapted to be moved in one direction to select groups of lines and to be moved in a second direction in a plane at right angles to the plane of first movement to a line in the elected group, a line relay for said connector switch controllable over the two sides of a calling one of said subscribers lines in series for controlling the movements of said contact makers, automatic ringing mechanism for said connector switch, means controlled by said line relay for associating said ringing mechanism with the called one of said subscribers lines, and substation-controlled means responsive to an act on the part of the called subscriber during a ringing interval to disconnect the ringing mechanism from the called subscribers line and during a silent interval to prevent a reapplication of ringing current from said ringing mechanism to said called subscribers line, said last means when actuated remaining in its actuated position until said connect-or switch is released.

32. A telephone system including a called subscribers line, a side-switchless connector switch for establishing connection therewith, contact makers for said switch, a magnet for moving said contact makers in one direction, a second magnet for moving said contact makers in another direction in a plane at right angles thereto, an impulse relay for said connector switch controllable over the two sides of a calling subscribers line in series, an auxiliary relay provided with individually controlled contacts for switching the impulse circuit controlled by said impulse relay from one of said magnets to the other of said magnets, a signaling generator, a ringing relay, means for connecting current from said signaling generator through the winding of said ringing relay to said called subscribers line, means for intermittently interrupting the circuit of said ringing current, and substation-controlled means responsive to an act on the part of the called subscriber for energizing said ringing relay during either a ringing or a silent period, and a locking circuit for said ringing relay independent of said energizing circuit. 7

A telephone system including a called subscribers line, a side-switchless connector switch for establishing connection therewith, contact makers for said switch, a magnet for moving said contact makers in one direction, a second magnet for moving said contact makers in another direction in a plane at right angles thereto, an impulse relay for said connector switch controllable over the two sides of a calling subscribers line in series, an auxiliary relay provided with individually controlled contacts for switching the impulse circuit controlled by said impulse relay from one of said magnets tothe other of said magnets, signaling current, a relay, automatic means for intermittently connecting said current through a winding of said relay to said called subscribers line,

said relay being adapted to be energized when the called subscriber responds during either a silent or a ringing period 'to disconnect said signaling current from said called subscribersline.

34. A telephone system including a called subscribers line, a side-switchless connector switch for establishing connection therewith, contact makers for said switch, a magnet for moving said contact makers in one direction, a second magnet for moving said contact makers in another direction in a plane at right angles thereto, an impulse relay for said connector switch controllable over the two sides of calling subscribers line in series, an auxiliary relay provided with individually controlled contacts for switching the impulse circuit controlled by said impulse relay t'rom one of said magnets to the other of said magnets, automatic ringing mechanism for said connector switch, means controlled by said line relay for associating said ringingmechanism with said called subscribers line. said ringing'mechanism being controllable by the response of the called subscriber to instantaneously disconnect or out off the ringing current from the called line, and means for preventing'a reapplication of ringing current to the called line until after the connector switch has been returned to normal and is again operated to connect with an idle line.

' Signed by me at Chicago in the county of Cook and State of Illinois, this 30th day of July, 1917.

GEORGE A. YANOCHOWSKI. 

